Iterative inflow-implicit outflow-explicit finite volume scheme for level-set equations on polyhedron meshes

In this paper, we propose a cell-centered finite volume method for advective and normal flows on polyhedron meshes which is second-order accurate in space and time for smooth solutions. In order to overcome a time restriction caused by CFL condition, an implicit time discretization of inflow fluxes and an explicit time discretization of outflow fluxes are used in an iterative procedure. For an efficient computation, an 1-ring face neighborhood structure is introduced. Since it is limited to access unknown variables in an 1-ring face neighborhood structure, an iterative procedure is proposed to resolve the limitation of assembled linear system. Two types of gradient approximations, an inflow-based gradient and an average-based gradient, are studied and compared from the point of numerical accuracy. Numerical schemes are tested for an advective and a normal flow of level-set functions illustrating a behavior of the proposed method for an implicit tracking of a smooth and a piecewise smooth interface.     

A successive estimation scheme of an occupation probability†

This paper treats of an estimation problem of an occupation probability of some targets in a Tegion M by an infra-red detector followed by a threshold device in a satellite.

First, a successive estimation scheme is proposed for an estimation problem of an occurrence probability of signal 1 of the 1,0 type binary signal sequence disturbed by some noise. The estimate obtained by this scheme is shown to converge to the true value with probability one and in the mean square. Then, as an application of this scheme for the occurrence probability, an estimation scheme for an occupation probability is proposed. Two examples illustrating the scheme for an occupation probability are presented.     

Roughness in MV-algebras

In this paper, by considering the notion of an MV-algebra, we consider a relationship between rough sets and MV-algebra theory. We introduce the notion of rough ideal with respect to an ideal of an MV-algebra, which is an extended notion of ideal in an MV-algebra, and we give some properties of the lower and the upper approximations in an MV-algebra.     

Automatic assembling procedure generation from mating conditions

A method is developed to automatically generate an assembling procedure for an assembly. In this work, an assembly is described by its components and their relationship in an assembly, especially the mating conditions. From the mating conditions of the components, an assembling procedure is generated in two steps. First, each component in an assembly is located at a specific vertex of a hierarchical tree. Second, an assembling procedure is generated from the hierarchical tree with the help of interference checking.     

Static and dynamic postural loadings during computer work in females: Sitting on an office chair versus sitting on an exercise ball

Seated computer work results in prolonged static loading, which has been associated with the development of musculoskeletal disorders. A popular alternative to sitting on an office chair while performing computer work is to sit on an exercise ball. Sitting on an exercise ball might affect static and dynamic aspects of working posture. We monitored posture, muscle activation and spinal shrinkage in 10 females performing a 1-h typing task, while sitting on an office chair with armrests and while sitting on an exercise ball. Sitting on an exercise ball resulted in 33% more trunk motion and in 66% more variation in lumbar EMG. Both of these findings can be considered to be an advantage for the exercise ball. However, the fifth percentile and average lumbar EMG were also higher when sitting on an exercise ball, with 38% and 78%, respectively. In addition, more spinal shrinkage occurred when sitting on an exercise ball than when sitting on an office chair. Arm flexion was reduced, but trapezius activation was unaffected when sitting on an exercise ball. It is concluded that the advantages with respect to physical loading of sitting on an exercise ball may not outweigh the disadvantages.     

An adaptive mixed finite element method for wind field adjustment

In this paper we present an adaptive strategy to obtain an incompressible wind field that adjusts to an experimental one, and verify boundary conditions of physical interest. We use an augmented lagrangian formulation for solving this problem. Our method is based on an Uzawa iteration to update the lagrange multiplier and on an elliptic adaptive inner iteration for velocity. Several examples show that the proposed method is efficient and reliable.     

Stabilization via homogeneous feedback controls

In this paper, we provide an explicit homogeneous feedback control with the requirement that a control Lyapunov function exists for an affine control system and satisfies an homogeneous condition. We use a modified version of the Sontag formula to achieve our main goal. Moreover, we prove that the existence of an homogeneous control Lyapunov function for an homogeneous affine system leads to an homogeneous closed-loop system by using the previous feedback control.     

企业内部供应链信息流集成 --上海精艺纺织制品加工厂集成化信息系统的建立

提出了以Intranet为基础 ,针对企业的实际现状 ,为企业进行管理咨询 ,选择适合企业的经营管理模式 ,并将其融入系统中 ,建立企业的集成化信息系统的设想。并以上海精艺纺织制品厂为实例 ,介绍了基于B/S架构的企业集成化信息系统的整体框架     

基于ISM的互操作性测试方法

协议测试中的互操作性测试是保证不同厂商通信设备之间能够正确实施互操作的主要工程测试方法。针对互操作性测试过程中缺乏形式化测试框架和测试方法指导而导致无法保证测试可靠性的问题,在介绍ETSI定义的通用互操作性测试模型基础上,提出一个基于互操作性状态机的互操作性测试方法。通过一个面向IPsec VPN的互操作性测试实例表明该方法的有效性和可行性。     

Time- and Space-optimal height-balanced 2-3 brother trees

The node-visit optimal (NVO) and the space-cost optimal (SCO) height-balanced (HB) 2-3 brother trees are defined. The characterization of the NVO HB 2-3 brother trees is developed. This characterization leads to a linear-time algorithm for constructing an NVO HB 2-3 brother tree for an ordered set of keys. The minimum space-cost of an N-key NVO HB2-3 brother tree and the space-cost of an N-key SCO HB 2-3 brother tree is analysed. It is shown that the minimum space-cost of an NVO HB 2-3 brother tree is never more than one plus the space-cost of an SCO HB 2-3 brother tree. Further, the minimum node-visit cost of an SCO HB 2-3 brother tree is at most one plus the node-visit cost of an NVO HB 2-3 brother tree. It is also shown that there exists an HB 2-3 brother tree which is both SCO and NVO for just over half the possible values of keys. Finally, an outline for constructing an SCO HB 2-3 brother tree is presented.     

Measurement-based modeling of contact forces and textures for haptic rendering

Haptic texture represents the fine-grained attributes of an object's surface and is related to physical characteristics such as roughness and stiffness. We introduce an interactive and mobile scanning system for the acquisition and synthesis of haptic textures that consists of a visually tracked handheld touch probe. The most novel aspect of our work is an estimation method for the contact stiffness of an object based solely on the acceleration and forces measured during stroking of its surface with the handheld probe. We establish an experimental relationship between the estimated stiffness and the contact stiffness observed during compression. We also measure the height-displacement profile of an object's surface enabling us to generate haptic textures. We show an example of mapping the textures on to a coarse surface mesh obtained with an image-based technique, but the textures may also be combined with coarse surface meshes obtained by manual modeling.     

A rule-based system for generating a ladder logic control program from a high-level systems model

In this article an interface between a high-level specification of a system and a logic controller of that system is developed. The interface is based on a number of rules to transform an IDEF0 specification into an intermediate-level Petri-net-based controller and to transform the intermediate specification into a ladder logic program which can be run on a PLC. These rules could be used as a basis for developing an expert system to handle the interface. Such an expert system provides an environment for rapid prototyping and analysis of controllers.     

Imperfect Evolutionary Systems

In this paper, we propose a change from a perfect paradigm to an imperfect paradigm in evolving intelligent systems. An imperfect evolutionary system (IES) is introduced as a new approach in an attempt to solve the problem of an intelligent system adapting to new challenges from its imperfect environment, with an emphasis on the incompleteness and continuity of intelligence. We define an IES as a system where intelligent individuals optimize their own utility, with the available resources, while adapting themselves to the new challenges from an evolving and imperfect environment. An individual and social learning paradigm (ISP) is presented as a general framework for developing IESs. A practical implementation of the ISP framework, an imperfect evolutionary market, is described. Through experimentation, we demonstrate the absorption of new information from an imperfect environment by artificial stock traders and the dissemination of new knowledge within an imperfect evolutionary market. Parameter sensitivity of the ISP framework is also studied by employing different levels of individual and social learning     

The XML Tree Model – toward an XML conceptual schema reversed from XML Schema Definition

XML Schema Definition (XSD) is the logical schemas of an XML model, but there is no standard format for the conceptual schema of an XML model. Therefore, we propose an XML Tree Model (XTM) as an XML conceptual schema for representing data semantics in a diagram, and also as an XML data model validator for confirming the data semantics required by users. An XTM consists of hierarchical nodes representing all the elements, and the data relationships among elements within the XSD. A rule-based algorithm and an information capacity with pre- and post-conditions are developed as the methodology for reverse engineering. The proposed algorithm consists of two rules: General Information Transformation and Data Semantic Recovering to construct an XTM. Users can draw an XTM with data relationships among elements as a result of the reverse engineering.     

在PB中自动配置ODBC数据源

在用PowerBuilder开发数据库应用程序时,经常需要配置ODBC数据源.手工配置ODBC不符合专业软件的要求,本文给出了一个在Windows系统中自动配置ODBC数据源的方法.     

The piecewise optimisation method for approximating uncertain optimal control problems under optimistic value criterion

In this paper, we introduce an approximate model and propose a piecewise optimisation method to simplify the expression of optimal control for an uncertain linear quadratic optimal control problem. First, we consider an optimal control problem of uncertain linear quadratic model under optimistic value criterion. Based on the equation of optimality, we deduce an analytic expression of optimal control. Then, we study an approximate model with control parameter and propose a piecewise optimisation method for solving the optimal parameter of such an approximate model. As an application, a four-wheel steering vehicle optimal control problem is given to show the utility of the proposed approximate model and the efficiency of the proposed piecewise optimisation method.     

具有可测强外扰作用的伺服系统应用二次型最优控制和最优观测器的工程实践

本文应用线性二次型最优控制理论设计了具有可测强外扰作用的伺服系统.该系统不仅 具有最优的状态反馈,而且具有最优的前馈补偿和外扰补偿,系统性能有明显的提高.文中还 介绍了当系统的状态不能直接量测时,最优状态观测器的设计问题.通过一个电液力伺服系 统的实例具体说明了设计步骤、计算结果和实验结果.     

3D convolutional neural network for object recognition: a review

Multimedia Tools and Applications - Recognition of an object from an image or image sequences is an important task in computer vision. It is an important low-level image processing operation and...